Telephone-transmitter.



N. TANNAKA.

TELEPHONE TRANSMITTER.

APPLICATION FlLED FEB. 14. 19w

1,252,051 I Patented Jan. 1, 1918.

- WIT/mums.- V INVENTOR- NAHO TANNAKA, 013 BOSTON, MASSACHUSETTS.

TELEPHONE-TRANSMITTER. I

Specification of LettersPatent.

Application filed February v1%;917. Serial No. 148,496.

To all whom it may concem:

Be it known that I, NAHO TANNAKA, 'a subject of the Emperor of Japan, residing at Boston, in the county of Suffolk and Commonwealth of Massachusetts, have invented new and useful Improvementsin Telephone- Transmitters, of which the following is a specification.

This invention relates to improvements in telephone transmitting apparatus, in which the entire working parts are yieldingly separated from their casing or stationary support, at least in the direction in which the diaphragm is destined to vibrate, so that the working parts are movable relatively to the casing in that direction, though within a minute or almost imperceptibly small limit. Although apparently for insulating and damping purposes, certain ordinary transmitters are provided with some separating means around the diaphragm. 'In

the present invention, cushioning means are employed not only around the diaphragm periphery, but also the back part or unit is independently cushioned against the casing, in a rigidityI sense, entirely or substantially insulating t e entire WOIklIlg parts from the latter, and preferably, similar provision IS further employed for connecting the front and back parts. In addition to an usual (mica) auxiliary diaphragm or aflexible sheeting, so that the front and back units and the casing are separated by cushions, one from the others. In operation, by proper adjustment of pressure thereon, these provisions of cushions seem to shift the current variation nearer to a sinusoidal form by modifying the magnitude of the increment and the decrement of the carbon cell resistance.

The chief objects of this invention are to provide apparatus in which sound, particularly voice, is translated into such electrical impulses that tend to produce sound at least of clear soft tone, without accompanying disagreeable harsh sound, or to transmit sound without distortion that seems to be inherent to the nowaday telephones, as far as the transmitting apparatus is concerned; first by applying my invention to my multiple carbon cell transmitter in which the resistance variability is at the same time increased, when the cells are connected in series, more in higher resistance circuits; second, by introducing this invention to ordinary transmitters of solid back type, viz., by a simple addition of parts thereto without discarding the original parts, so that ordinary pieces of apparatus may be easily convertible into the new type with a very little additional outlay. I attain to the above ob- Patented Jan. 1, 1918- jects by constructing apparatus as herein shown and described.

With the above and other objects in view this invention comprises certain detail 0 eonstruction and arrangements .of parts, :as will be hereinafter more fully described, illustrated and claimed.

The invention willbe best understood from the following description taken in connectionwith the accompanying drawings, forming a part of this specification, in which similar numerals of reference indicate similar or corresponding parts throughout the several views, and in which Figure 1 is a vertical central section, partly in elevation, of a multi-cell transmitter embodying m invention; Fig. 2, a

partly broken back view of the same, illustrating the inner structure; Fig. 3, a vertical central section of a transmitter, similarly embodying this invention, as applied to a transmitter of solid back type; and Fig. 4:, a

broken back view of the above.

Referring to Figs. 1 and 2, ldesignates a front plate which has two edged rings 2 and 3. The front ring 2 attached thereto at the rear face, or preferably the front plate is shaped to form the front ring, and the back ring '3- through its flanges (which may be flexible) is attached to the front plate by means of screws, but the latter ring maybe attached to aback support or bridge which will be referred to later. To be sure, the front plate has an opening to receive a customary mouth-piece.

Disposed between the rings 2 and 8, a diaphragm or vibrator 4 carries a rubber (or the like) collar orcushions 5 at its peripheral portion, the rings compressingly or compressively holding the diaphragm through the cushions.

By means of screws 6, having small or light shanks 7 and nuts 8, front electrodes 9 being plated and soldered to the shanks are I secured to the diaphragm 4 as shown, constituting a vibratory unit or part.

At'the rear of the front plate 1, a bridge or support 10 is yieldingly or elastically attached thereto through cushioning washers or pads 11, such as of 'felt or soft rubber,

which are held together under pressure with the support between the edge of the front plate and guard pieces 12 by screws 13 which pass loosely through holes of the sup port 10, or through bushings 14: provided in the holes. (See Fi 4..)

Adjust'ably attached to the support or bridge by an usual screw-means, a plurally cup-shaped piece 15 bears insulated back electrodes 16 at the cup bottoms, forming a back unit or part.

Covering the mouths of the cups, a ilexible sheeting 17 is secured between the cup piece 15 and a guard plate 18 the latter having perforations which coincide with the cup mouths. The sheeting and the vibratory unit are yieldingly connected through ring cushions 19, such as of felt or soft rubber, which are held together with the sheeting between the shanks 7 and the back nuts 8, thescrew stems 6 passing through the perforations of the sheeting and the cushions, and are disposed in such manner that each pair of the front and back electrodes confront in parallel within a closed chamber formed thereby. Variable resistance mediums or granular carbon 20 are placed in the chambers. The carbon cells thus formed are joined preferably in series, either by insulating one of the front electrodes from the diaphragm, or employing a diaphragm of suitable insulating material.

In Figs. 3 and 4, a bridge 10, which corresponds to the support 10 of Figs. 1 and 2, is

similarly cushioned by yielding washers or pads 11 at the ends thereof. The bridge carries a cup or case 21 which contains a back electrode 16 and granular carbon 20 said cup and electrode forming a back unit. A diaphragm a at the front thereof has a rubber band collar 5 and is pressed by customary damping springs with yielding pads (not shown) against a front plate 1, and a front electrode 9 is mounted on the diaphragm as before, constituting a vibratory unit. These two units are connected by a sheeting 17 and washers 19 in a similar manner previously described referring to Figs. 1 and 2.

I wish to have it understood that the construction and arrangement of parts 'shoWn in or described for one form is similarly applicable to the other.

.From the foreging description taken in connection with the accompanying drawings, the advantage of the construction and the arrangements of parts and the method of operation will be readily apparent to those skilled in the art to. which this invention appertains, and while I have herein set forth the invention in what is now thought bination with a casing; of front and back electrodes bearing units, cushions between the casing and the said two units, the units being independently attached to the casing through the cushions, and parts constituting therewith a variable resistance device.

2. In a telephone transmitter, a yieldin mounting for the. working parts thereo comprising a casing, a back support, and

cushions separately held between the Working parts and the casing, and between the back support and the casing, the working parts and the supports being independently attached to the casing.

3. In a telephone transmitter, the combination with a casing, a vibratory unit,'a back unit elastic-ally separated romthc vibratory unit, and granular carbon between the units; of two sets of cushions, each set separatingone of the said two units from the casing which holds the said units separately through the cushions.

fl. In a telephone transmitter, a casing, a diaphragm attached to the casing, a variable resistancevcombination connected to the diaphragm, cushion means, and a rigid support holding the said resistance combination and attached to the casing through the cushioning means independently of the diaphragm.

5. In a telephonic apparatus,-t-he combination with a casing, a variable resistance unit comprising front and back electrode bearing elements and granular carbon; of elastically mounting means for the resistance unit, rovided between the casing and the front 0 ectrode bearing element, and between the casing and the back electrode bearing element, the electrode elements being held thereby, each independently of the other.

6. A telephone transmitter, provided with a casing, a vibrator held by the casing, cushions, a back unit elastically separated from the vibrator and yieldingly attached to the casing through the cushions, independently of the vibrator, and variable resistance material between the vibrator and the back unit.

7. A telephone transmitter, provided with a casing, a vibratory unit, a back unit, and cushions between every pair of the above parts, the said vibratory and back units Hill 8. In a telephone transmitter, the combination with a casing, vibratory and back units elastically connected together and having a variable resistance medium therebetween; of cushions disposed and separately held between the said units and the casing, so as to permit the units to move relatively to the casing, at least, in the direction in which the vibratory unit is destined to vibrate.

9. A telephone transmitter, provided with a casing, front and back electrode bearers,

anular carbon, a sheeting attached to one of the said electrode bearers and yieldingly connected to the other bearer, and cushions which separate the said electrode bearers from the casing, the casing separately holding the bearers through the cushions.

10. In a telephonic apparatus, the combinationwith a casing, a vibratory unit, a back unit, and anular carbon between the units; 'of a flexible sheeting attached to one of the said units, cushions held together with the. sheeting by the other unit, and other cushions through which the said units are independently attached to the casing.

11. In a telephone transmitter, a casing, a diaphragm, cushions for the diaphragm, a variable resistance unit cooperatively related to the diaphragm, a support for the said resistance unit, holding means for the support adjustably attached to the casing, and other cushions between the support and the said means, the-said two sets of the cushions being separately held by the casing under pressure. V

12. In a variable resistance device, a casing, a diaphragm, a front padding through which the diaphragm is held by the casing, a back'support, a back padding disposed on opposite sides of the support, screw means adapted to engage with the casing for holding the support and the last mentioned padding together separately from the diaphragm, and variable resistance mediums cooperatively related thereto.

13. A telephone transmitter, provided with v a vibratory part having a cushioned diaphragm, a casing having ro ections for olding the diaphragm, a ack part, and

cushions for,- .,the back part held therewith together by the casing separately from the diaphragm.

14. A telephone transmitter, provided with a casing, a vibrator, a cushioning element, a back part held by the casing and elas tically attached to the vibrator, projecting members held in the casing and holding the vibrator and the cushioning element together, the'bro'ecting members being shaped and relating t .the cushioning element in such manner comparatively small part of the latter is eflectually under pressure,

and a variable resistance medium in 006peratlve relation thereto.

15. In a telephone transmitting apparatus,

front ,and back electrode bearers, a casing.

i a mounting yieldingly connectingthe support to the casing independently of the said cushions; with a variable resistance unit.

17 In a .telephonetransmitter, a cush-v ioned diaphragm, a casing. havin rojec- 'tions in contact with the cushion o t e diaphragm, elastically pressing means which coiiperate with the projections in holding the diaphragm compressively' therebetween, a back support, a padding separating the support from the casing, and variable resist: ance means in coiiperative relation thereto.

18. In a telephonetransmitter, the combination of a casing having edged rings, a cushioned diaphragm held between the rings, a back unit, a support for the back unit, and a cushion mounting for the support, held therewith together under pressure by the casing and its attachments; with parts constituting therewith, a variable resistance device.

19. A telephone apparatus, provided with a yielding mounting for the vibratory part thereof, comprising a back part, a sheeting yieldingly connected to one of the said two parts and rigidly to the other, a casing holding the back art, cushions on opposite sides of the vi ratory part, and members having narrow edges for holding the vibratory part through the cushions.

20. A telephone transmitter, provided with a casing having a projection or shoulder which terminates with a narrow edge, pressing means attached to the casing, a cushioned diaphragm held between the said means and the projection or shoulder, cushioning means, a support attached to the casing through the said cushioning means; and a variable resistance medium cooperatively related thereto.

21. In a telephone transmitter, a casing, a vibratory unit elastically held thereby, a support yieldingly attached to the casing, a back unit held by the support, cushions, and a flexible sheetin attached to one of the said two units, which has cups or cases containing electrodes and granular carbon, and yieldingly connected to the other um through the cushions. I a 22. In a telephone transmitter, a casing, a vibratory unit cushioned against the easing and held thereby, cushioning washers, In testimony whereof Iaifix my signature :1 bacilli uni? elasticalg mountedb on the casin presence of two subscribing Witnesses. in f; rougl the Was ers, a car on c0ntaining case carrieci by one of the said two units, TANNAKA' 5 a sheeting attached to the case, and pads held Witnesses:

together with the sheeting by the other of UsAMU H. TERADA, zhe said units. TonAo TANAKA. 

